I willing to try really hard on working with Very Low Frequency waves to get a signal through the earth a few Km.

How can I go about putting a signal at the frequency (probably near 10 kilohertz) into the ground?

I have been searching for schematics everywhere, but just nothing shows up.

I know it is possible, I have seen some amateur radio really low frequency contacts through the earth.

I know it is slow-speed CW, but that is still worth the joy of experimenting.

Can I use ground rods instead of a HUGE antenna?

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    $\begingroup$ This shows very little research effort. What exactly are you asking, beyond "please design an ELF/LF transmitter for me with these parts I have"? $\endgroup$ – Phil Frost - W8II Jan 6 '14 at 14:18
  • $\begingroup$ ELF as per en.wikipedia.org/wiki/Extremely_low_frequency is 3-30 Hz, you're talking about VLF which as per en.wikipedia.org/wiki/Very_low_frequency is 3-30 KHz. $\endgroup$ – K7AAY Jan 8 '14 at 4:34
  • $\begingroup$ Transmitting; Match an Audio Amplifier output impedance to the Ground rods. Receiving; Match the Audio Amplifier input impedance to the Ground rods. Space the rods a good distance apart. $\endgroup$ – Optionparty Jan 19 '14 at 0:43

The point of a huge antenna is efficiency. Ground rods alone will result in a very small signal being received, and high transmitter mismatch. VLF antennas are massive and require both very large grounding radials as well as antennas.

The links from the VLF page at Wikipedia, especially the Long Wave Radio Club of America and K4NYW's page on vintage Navy radio gear has some schematics. If you can find a schematic for an AN/FRT-96 which was still in use by the USN as of two years ago, you'll be in business. Perhaps a search on LinkedIn for folks who list that in their skill set might help.


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